Size Matters


So just went and helped get a buddy fit for a mountain bike today. Insights from the experience:

  • First off...manufacturer size recommendations are general guidelines. DON'T buy a bike based on those size recommendations WITHOUT actually going into a shop and riding the bike unless you are absolutely positive that it is the size you need. Ideally, you should demo the bike on your local trail(s) but if that's not possible RIDE THE BIKE before you buy it...and not just the parking lot...go around the block. Something that allows you to actually have to change positions and shift gears for more than just 3-5 minutes.
  • your homework before you get to the shop. Know what size the company recommends for you so that you know when you get into the shop if you're on the fringe between two sizes. If you're in the 5'8" to 5'11" height range then you are highly likely to be on the cusp of a Medium or a Large depending on the manufacturer of your target bike.

My buddy is 5'10" and had one shop guy telling him he needed a medium, and yet another recommending a large. The company website specified a range of 5'8"-6'2" for their large frames. The following day, I accompanied him to the shop and requested that they let him RIDE both sizes. As I expected, the medium was a tad small and he didn't look comfortable or confident. We rode around the block and then to a low traffic parking lot and I watched him ride then decided to go back and try a large from the same manufacturer but slightly different frame. The geometry was very near identical and it was the same company so we gave it a shot. Right out the door, as soon as he started pedaling on the large, it was a night and day difference...he took off like a dog that spotted an open gate out of the backyard. Entirely more comfortable...entirely more confident. So he ordered the large of the model he was originally targeting with a slightly shorter stem than the company stocked and after reviewing the numbers, his final bike will have a reach .01" longer than the setup he rode today.

Moral of the story...GO RIDE the bike you're interested in. Have them fit you to the bike...and make sure you find a shop with staff that doesn't make you feel like they've got something better to do than set you up or answer your questions. From a bike shop perspective though, keep in mind that it could be a time consuming event so don't walk in 30 minutes prior to closing and expect a fitting either. To be fair, my buddy went in yesterday a little after 5 and the shop closes at 6. Even that being said though...the misinformation/conflicting information wasn't cool. I feel that they would have done better to offer him an opportunity for an appointment to fit him to a bike...and they didn't. We had to suggest riding the bike(s) today to see which would be the better option...instead of having that opportunity offered to us.